Carnegie stage 18

Introduction

Facts

Week 7, 44 - 48 days, 13 - 17 mm

Events

Ectoderm: sensory placodes, lens pit, otocyst,nasal pits moved ventrally, fourth ventricle of brain

Mesoderm: heart prominence

Head: 1st, 2nd and 3rd pharyngeal arch, forebrain, eye, auricular hillocks

Body: heart, liver, umbilical cord

Limb: upper and lower limb buds, foot plate, wrist, hand plate with digital rays

Features

Identify: pigmented eye, eyelid, nasolacrimal groove, external acoustic meatus, heart, digital rays, liver prominance, thigh, ankle, foot plate, umbilical cord

Carnegie Stages: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | About Stages | Timeline

Bright Field

Embryo in gestational sac	Embryo open sac

Kyoto Collection

View: This is a dorsolateral view of embryo. Amniotic membrane removed.

Image source: Embryology page Created: 19.03.1999

Image source: The Kyoto Collection images are reproduced with the permission of Prof. Kohei Shiota and Prof. Shigehito Yamada, Anatomy and Developmental Biology, Kyoto University Graduate School of Medicine, Kyoto, Japan for educational purposes only and cannot be reproduced electronically or in writing without permission.

Carnegie Collection

Carnegie stage 18: Right | Anterior | Posterior | Left | Right | Anterior | Posterior | Left

Additional Images

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  External ear Stages 14-23 and adult

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  Human embryonic shoulder girdle

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  17 mm Embryo

Carnegie Stages: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | About Stages | Timeline

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Cite this page: Hill, M.A. (2024, May 2) Embryology Carnegie stage 18. Retrieved from https://embryology.med.unsw.edu.au/embryology/index.php/Carnegie_stage_18

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© Dr Mark Hill 2024, UNSW Embryology ISBN: 978 0 7334 2609 4 - UNSW CRICOS Provider Code No. 00098G